SDHA encodes a major catalytic subunit of succinate-ubiquinone oxidoreductase, a complex of the mitochondrial respiratory chain. The complex is composed of four nuclear-encoded subunits and is localized in the mitochondrial inner membrane. Mutations in this gene have been associated with a form of mitochondrial respiratory chain deficiency known as Leigh Syndrome. A pseudogene has been identified on chromosome 3q29.

Hirawake et al. (1994) isolated a cDNA corresponding to the flavoprotein subunit of SDH from a human liver cDNA library. The deduced 621-amino acid protein has a molecular mass of approximately 68 kD and shows high homology to the bovine heart flavoprotein subunit.